Thermal processing torches, such as plasma arc torches, are widely used for high temperature processing (e.g., heating, cutting, gouging and marking) of materials. A plasma arc torch generally includes a torch head, an electrode mounted within the torch head, an emissive insert disposed within a bore of the electrode, a nozzle with a central exit orifice mounted within the torch head, a shield, electrical connections, passages for cooling, passages for arc control fluids (e.g., plasma gas) and a power supply. A swirl ring can be used to control fluid flow patterns in the plasma chamber formed between the electrode and the nozzle. In some torches, a retaining cap is used to maintain the nozzle and/or swirl ring in the plasma arc torch. In operation, the torch produces a plasma arc, which is a constricted jet of an ionized gas with high temperature and sufficient momentum to assist with removal of molten metal. Gases used in the torch can be non-reactive (e.g., argon or nitrogen), or reactive (e.g., oxygen or air).
Existing plasma arc torches require the use of multiple distinct consumable components that need to be individually assembled into each torch and in a specific order/orientation to enable proper torch operation. FIG. 7 shows an exemplary configuration of such a conventional plasma arc torch. In some cases, two or more consumable components of a torch can be combined into a cartridge to reduce part count, improve part maintenance, and facilitate torch operation. However, improvements are still needed to further simplify torch parts and enhance installation and removal of consumable components relative to a torch. For example, given a unitary cartridge of multiple consumable components, it is difficult to install the cartridge onto a torch body because multiple components of the cartridge, thus multiple engagement surfaces, need to be oriented and aligned correctly with the torch body to achieve engagement. Further, improvements are needed to allow components in a torch to be easily accessible and serviceable.